In U.S. Pat. No. 3,185,336, Goss discloses a cover assembly designed to completely enclose and protect the valves on tanks used to contain noxious and inflammable gases and liquids. A circular collar with a front locking lug and rear projecting guide lugs is welded to the cylinder around the valves. Openings in the bottom of the collar permit drainage of water that may accumulate within the enclosure. A cylindrical cap with a flat top and circumference slightly larger than the collar fits down over the collar. The cap is hingedly attached to the rear guide lugs and can be padlocked through the front locking lug. The design is such that even if the hinge bolt is removed, the cap cannot be lifted to expose the valves with the padlock in place.
Callegari et al., in U.S. Pat. No. 5,238,141, teaches a locking cover for liquid propane tanks. This cover is designed for propane tanks having a fully exposed valve and no attached collar. A circular base plate having a slot is slipped around the valve and sits on the shoulder of the tank. A hinged cup shaped cap rotates down to the base plate and completely encloses the valve. A lock flange on the base plate cooperates with a flange on the cap to accommodate a padlock to secure the valve. An additional locking ring can be added to prevent anyone from reaching in through the slot to contact the valve.
The valves of tanks used to ship and store a variety of chemicals can be protected by a cover assembly having a collar that is rigidly attached to the tank. A lid is attached to the collar by a hinge designed with a stop means such that the hinge can be opened to an upright position but will not flop backward to hit the side of the tank. There are several sets of pivotally attached bolts that cooperate with sets of flanges on the lid to seal and maintain the lid closed. An O-ring can be fitted into the lid to completely seal the valve area. This assembly is taught by Creaghe in U.S. Pat. No. 5,690,141.
Petryna teaches a child proof cover for compressed gas valves for the smaller tanks commonly used with home barbecue systems. The cover is a cylindrical housing formed in two hinged sections that clamp together around the valve. The sides of the housing taper downward so that once clamped in place it cannot be lifted to expose the valve. An opening in the side of the housing permits the regulator to extend out of the housing while the valve is totally within the housing. A top is hinged to the housing and various embodiments require a rotation of the top to gain access to the valve. (U.S. Pat. No. 6,247,491)
A dual purpose propane tank cover assembly is taught by Hill in U.S. Pat. No. 7,322,487. This assembly is for use with small propane tanks used with home barbecues and enables the propane tank to be used as a table while protecting the tank's valve system. A cap fits within the tank's collar and cooperates with the slots in the sides of the collar to completely enclose the valves. There is also a hinged outer collar that locks around the tank collar and supports a circular plate that extends above the collar. A round table top with a track mounted on its underside fits over the plate and prevents the table top from shifting. This assembly creates a table which can be covered with a cloth to completely hide the tank.
There is a need for a single cover assembly for large commercial and residential propane tanks that can be used with the tanks of all manufacturers. There is a need for such a cover that can be taken from one tank and used on another tank of the same size made by the same or a different manufacturer. There is a need for a tank cover assembly that will not rust or corrode and enables the cover to be hingedly attached to the propane tank and remain closed to protect the valves and gauges.